Aren
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TLJ
The common currency of Ayrede, Aren are small iron coins. We don't find out the exact value of one Aren, but Karek pays April one Aren per map delivery, and Captain Horatio Nebevay tips her one when she delivers to him. Benrime is generous enough to give April a whole handful of them when she discovers she is without money. As an Aren is made of iron, one could be forgiven for deriving its origin from the Germanic word 'iron' (OE iren). Its similarity to the word Ayrede no doubt also worked in its favour.
When April tries to play the cups game with her gold ring as payment, the Cups Handler tells her that he doesn't accept gold as payment. Iron, however, is a valuable commodity in Arcadia. This may explain why Arcadia's technological development is so limited.
In much the same way that April finds her Screwdriver, Calculator and Organic Plastic Leaf handy in Arcadia, a spare Aren she has in her pocket comes in handy on the Morning Star when she needs to unscrew an air duct. Unlike the latter two items, however, its use in Stark exhibits no unusual properties.
Dreamfall
By the time of Dreamfall the currency appears to have changed to gold, as is evidenced when Benrime brings up Brian's bar tab and he counters that he is about to collect some gold owed to him. This may have something to do with the low value of iron amongst the Azadi, who appear to have the metal in abundance.
